The author's intention to publish his MSS.

The author's intention to publish his MSS.

1.

How by a certain machine many may stay some time under water. And
how and wherefore I do not describe my method of remaining under
water and how long I can remain without eating. And I do not publish
nor divulge these, by reason of the evil nature of men, who would
use them for assassinations at the bottom of the sea by destroying
ships, and sinking them, together with the men in them. Nevertheless
I will impart others, which are not dangerous because the mouth of
the tube through which you breathe is above the water, supported on
air sacks or cork.

[Footnote: The leaf on which this passage is written, is headed with
the words _Casi_ 39, and most of these cases begin with the word
'_Come_', like the two here given, which are the 26th and 27th. 7.
_Sughero_. In the Codex Antlanticus 377a; 1170a there is a sketch,
drawn with the pen, representing a man with a tube in his mouth, and
at the farther end of the tube a disk. By the tube the word
'_Channa_' is written, and by the disk the word '_sughero_'.]

The preparation of the MSS. for publication.

2.

When you put together the science of the motions of water, remember
to include under each proposition its application and use, in order
that this science may not be useless.--

[Footnote: A comparatively small portion of Leonardo's notes on
water-power was published at Bologna in 1828, under the title: "_Del
moto e misura dell'Acqua, di L. da Vinci_".]

Admonition to readers.

3.

Let no man who is not a Mathematician read the elements of my work.

The disorder in the MSS.

4.

Begun at Florence, in the house of Piero di Braccio Martelli, on the
22nd day of March 1508. And this is to be a collection without
order, taken from many papers which I have copied here, hoping to
arrange them later each in its place, according to the subjects of
which they may treat. But I believe that before I am at the end of
this [task] I shall have to repeat the same things several times;
for which, O reader! do not blame me, for the subjects are many and
memory cannot retain them [all] and say: 'I will not write this
because I wrote it before.' And if I wished to avoid falling into
this fault, it would be necessary in every case when I wanted to
copy [a passage] that, not to repeat myself, I should read over all
that had gone before; and all the more since the intervals are long
between one time of writing and the next.

[Footnote: 1. In the history of Florence in the early part of the
XVIth century _Piero di Braccio Martelli_ is frequently mentioned as
_Commissario della Signoria_. He was famous for his learning and at
his death left four books on Mathematics ready for the press; comp.
LITTA, _Famiglie celebri Italiane_, _Famiglia Martelli di
Firenze_.--In the Official Catalogue of MSS. in the Brit. Mus., New
Series Vol. I., where this passage is printed, _Barto_ has been
wrongly given for Braccio.

2. _addi 22 di marzo 1508_. The Christian era was computed in
Florence at that time from the Incarnation (Lady day, March 25th).
Hence this should be 1509 by our reckoning.

3. _racolto tratto di molte carte le quali io ho qui copiate_. We
must suppose that Leonardo means that he has copied out his own MSS.
and not those of others. The first thirteen leaves of the MS. in the
Brit. Mus. are a fair copy of some notes on physics.]

Suggestions for the arrangement of MSS treating of particular
subjects.(5-8).

5.

Of digging a canal. Put this in the Book of useful inventions and in
proving them bring forward the propositions already proved. And this
is the proper order; since if you wished to show the usefulness of
any plan you would be obliged again to devise new machines to prove
its utility and thus would confuse the order of the forty Books and
also the order of the diagrams; that is to say you would have to mix
up practice with theory, which would produce a confused and
incoherent work.

6.

I am not to blame for putting forward, in the course of my work on
science, any general rule derived from a previous conclusion.

7.

The Book of the science of Mechanics must precede the Book of useful
inventions.--Have your books on anatomy bound! [Footnote: 4. The
numerous notes on anatomy written on loose leaves and now in the
Royal collection at Windsor can best be classified in four Books,
corresponding to the different character and size of the paper. When
Leonardo speaks of '_li tua libri di notomia_', he probably means
the MSS. which still exist; if this hypothesis is correct the
present condition of these leaves might seem to prove that he only
carried out his purpose with one of the Books on anatomy. A borrowed
book on Anatomy is mentioned in F.O.]

8.

The order of your book must proceed on this plan: first simple
beams, then (those) supported from below, then suspended in part,
then wholly [suspended]. Then beams as supporting other weights
[Footnote: 4. Leonardo's notes on Mechanics are extraordinarily
numerous; but, for the reasons assigned in my introduction, they
have not been included in the present work.].

General introductions to the book on Painting (9-13).

9.

INTRODUCTION.

Seeing that I can find no subject specially useful or
pleasing--since the men who have come before me have taken for their
own every useful or necessary theme--I must do like one who, being
poor, comes last to the fair, and can find no other way of providing
himself than by taking all the things already seen by other buyers,
and not taken but refused by reason of their lesser value. I, then,
will load my humble pack with this despised and rejected
merchandise, the refuse of so many buyers; and will go about to
distribute it, not indeed in great cities, but in the poorer towns,
taking such a price as the wares I offer may be worth. [Footnote: It
need hardly be pointed out that there is in this 'Proemio' a covert
irony. In the second and third prefaces, Leonardo characterises his
rivals and opponents more closely. His protest is directed against
Neo-latinism as professed by most of the humanists of his time; its
futility is now no longer questioned.]

10.

INTRODUCTION.

I know that many will call this useless work [Footnote: 3. questa
essere opera inutile. By opera we must here understand libro di
pittura and particularly the treatise on Perspective.]; and they
will be those of whom Demetrius [Footnote: 4. Demetrio. "With regard
to the passage attributed to Demetrius", Dr. H. MÜLLER STRÜBING
writes, "I know not what to make of it. It is certainly not
Demetrius Phalereus that is meant and it can hardly be Demetrius
Poliorcetes. Who then can it be--for the name is a very common one?
It may be a clerical error for Demades and the maxim is quite in the
spirit of his writings I have not however been able to find any
corresponding passage either in the 'Fragments' (C. MULLER, _Orat.
Att._, II. 441) nor in the Supplements collected by DIETZ (_Rhein.
Mus._, vol. 29, p. 108)."

The same passage occurs as a simple Memorandum in the MS. Tr. 57,
apparently as a note for this '_Proemio_' thus affording some data
as to the time where these introductions were written.] declared
that he took no more account of the wind that came out their mouth
in words, than of that they expelled from their lower parts: men who
desire nothing but material riches and are absolutely devoid of that
of wisdom, which is the food and the only true riches of the mind.
For so much more worthy as the soul is than the body, so much more
noble are the possessions of the soul than those of the body. And
often, when I see one of these men take this work in his hand, I
wonder that he does not put it to his nose, like a monkey, or ask me
if it is something good to eat.

[Footnote: In the original, the Proemio dì prospettiva cioè
dell'uffitio dell'occhio (see No. 21) stands between this and the
preceding one, No. 9.]